This invention relates to optical fiber communication systems and, particularly, to a connector for connecting two optical fibers used in such systems.
In an optical communication system, it is necessary to couple optical fibers end-to-end, as well as to devices such as detectors or signal generators. Coupling of optical fibers in end-to-end relationship is a difficult task, particularly when high coupling efficiencies are required. Any axial misalignment of the fibers in the coupling will attenuate the signal across the coupling.
In the past, connectors have been built which do provide good axial alignment for fibers to be connected. However, building of such connectors requires a number of difficult machining operations in order to reduce the tolerance build-up between the connector parts, or requires conditions of assembly which, while fairly readily attainable in the laboratory, are not easily obtained in the field. Ideally, an optical fiber connector should be relatively simple, inexpensive, be capable of being coupled and uncoupled many times without degradation of coupling efficiency, and provide accurate axial alignment between two optical fibers.
Therefore, it is an object to provide another optical fiber connector which provides good axial alignment between two optical fibers.
Another object is to provide a relatively low cost optical fiber connector.
Yet another object is to provide an optical fiber connector which utilizes commercially available, low cost precision components.
These and other objects of the invention are realized in one illustrative embodiment thereof wherein an optical fiber connector has a male connector portion having at least three cylindrical inner rods held in tangential contact with each other forming an opening which contains an optical fiber. A female connector portion has at least three cylindrical outer rods arranged to form a nest to accommodate the inner rods. Nesting of the inner rods within the outer rods positions the fiber, with a high degree of accuracy, within the female connector portion.
A feature of the invention is arrangement of the outer rods so that they form a nest to accommodate the inner rods. This arrangement permits accurate positioning of the fiber within the female connector.
Another feature of the invention is that the nest formed by the outer rods accommodates end-to-end the inner rods of two substantially identical male connector portions, thereby permitting accurate positioning and axial alignment in the end-to-end coupling of the fibers held by the two male connector portions.
Another feature of the invention is that each outer rod contacts at least one inner rod to thereby fixedly position the optical fiber.
Another feature of the invention is that each inner and outer rod is a precision bearing roller, which is a low cost, commercially available item.
Yet another feature is that the outer rods are in tangential contact with each other. This arrangement permits precise control of the size of the nest formed by the outer rods.